Railway signaling



April 6, 1937. G. R. PFLASTERER RAILWAY S IGNALING 2 Sheets-Shee'I. 1

Filed March 14, 1936 April 6, 1937- G. R. PFLAsTl-:RER

I RAILWAY SIGNALING Filed March 14, A1936 2 Sheets-Sheet 2 sterer ATTORN EY PGN mwN NN +L ELU Q mw Y Y@ W NA Patented Apr. 6, 1937 UNITED STATES PATENT OFFICE RAILWAY SIGNALIN G `.familianim March 14, 193s, serial No. 68,808

13 Claims.

My invention relates to railway signaling, and particularly to signaling involving wayside signals located along a trackway for governing the passage of trains.

A feature of my invention is the provision of novel and improved apparatus for establishing a distinctive control for each of three sections in the rear of an occupied section. Each distinctive control is effective to cause a corre- 10 spending aspect of the associated wayside signal whereby there is produced a three-block,

four-indication, system of signaling.

I will describe one form of apparatus embodying my invention, and will then point out the l5 novel features thereof in claims.

In the accompanying drawings, Figs. lA and 1B are diagrammatic views which when placed end to end in the order named illustrate one form of apparatus embodying my invention( Referring to the drawings, the reference characters 8 and 9 designate the rails of a stretch of railway track along which traffic normally moves in the direction indicated by the arrows. These rails are divided by insulated joints I4 into a plurality of track sections W--X, X-Y. and Y-Z.

As here shown, each track section is divided by insulated joints I 4 into at least two subsections IT, 2T, 3T, 4T, etc. Each subsection is rO provided with a track circuit which includes a track battery i5 connected across the rails at one end of the subsection and a track relay, designated by the reference character TR with a prefix the same as the numerical prex inthe reference character of the associated subsection, connected across the rails at the other end of the subsection.

To govern the passage of trains through the stretch of railway, a wayside signal, designated 40 by a suitable distinguishing reference character, is provided for each track section. Each of these signals includes an upper unit U and a lower unit L. These units may take any one of several forms of signal mechanism such as semaphore, color light, searchlight, or position light. As here shown, each upper unit U is a semaphore arm capable of assuming a horizontal or stop position, a 45 or "caution position, and a vertical or proceed position; and each lower unit L is a semaphore arm capable of assuming a horizontal or a vertical position but not a 45 position.

For controlling the associated signal, each section is provided with a polarized signal control relay and with a neutral signal control relay designated by the reference characters Hand J, respectively, each with a prefix the same as the reference character of the associated signal. l

For controlling the associated relay H, each section is provided with a polarized line circuit which includes a pair of line wires extending to the signal next in advance. For governing the associated relay J, each section is provided with a neutral line circuit which includes another line wire extending to the signal next in advance and one wire of the associated polarized circuit. Each of the three line wires is governed by each of the associated track relays.

Each relay H is directly connected to the associated polarized line circuit and each relay J is connected directly to the associated neutral line circuit.

For supplying energy for the system, each section is provided with a suitable source of energy the terminals of which are designated by the 'd reference characters B and C.

As will be explained more in detail hereinafter, the relays H and J control both the polarized and neutral line circuits for the section next in rear. '2'

The relays I-I and J control the upper unit U and the lower unity L ofthe associated signal in the followingmanner: When relay H is deenergized (see signal I3) both semaphore arms are in the horizontal position so that signal I3 is indicating stop. When relay H is energized in the reverse direction and relay J is deenergized (see signal I2), a caution circuit for the semaphore arm U of that signal is closed over a path which passes from terminal B through front contact I'I of relay I2H, and semaphore arm U to terminal C. Signal I2, therefore, is displaying its semaphore arm U in the caution position and its semaphore arm L is in the horizontal position to indicate approach next signal prepared to stop. When relay I-I is energized in the reverse direction and relay J also is energized (see signal I I), the caution circuit for semaphore arm U remains closed over front contact Il of relay III-I, and a proceed circuit for lower semaphore arm L is closed over a path which passes from terminal B through front contact I'l of relay IIH, reverse polar contact I8-I9 of relay I IH, and front point of contact 20 of relay IIJ to semaphore arm L and terminal C. Signal II, therefore, is displaying its upper semaphore arm U in the caution position and its lower semaphore arm L in the proceed position to indicate approach next signal at medium speed. When relay H is energized in the normal direction (see signal IU), the cauf tion circuit for upper semaphore arm U remains closed over front contact I'I of relay IilH, and a. proceed circuit for semaphore arm U is closed over a path which passes from terminal B through front contact I1 of relay IDH, and normal polar contact I8-2I of relay IH to semaphore arm U and terminal C. Signal I0, therefore, is displaying its upper semaphore arm U in the proceed position and its lower semaphore arm L in the horizontal position to indicate proceed at normal speed.

As here shown, a train K is indicated diagrammatically in the section immediately to the right of location Z. Consequently, both line circuits for that section are opened so that both relays I3H and I 3J are deenergized.

When relay I 3H is deenergized, relay I2H is energized in the reverse direction over a circuit which passes from terminal B at signal I3, through back point of contact 22 of relay iBH, front contact 23 of relay STR, front contact 24 of relay 5TR, relay I2H, front contact 25 of relay STR, front contact 26 of relay STR, and back point of contact 2'I of relay I3H to terminal C.

When relay I2H is energized in the reverse direction and relay I2J is deenergized, relay HH is energized in the reverse direction over a cir cuit which passes from terminal B at signal I2 through back point of contact 23 of relay IZJ, reverse polar contact 29-30 of relay I2H, front point of contact 3l of relay I2H, front contact 32 of relay 4TR, front contact 33 of relay 3TR, relay IIH, front contact 34 of relay 3TR, front contact 35 of relay 4TR, front point of contact 36 of relay I2H, reverse polar contact 3I-38 of relay I2H, and back point of contact 39 of relay I2J to terminal C; and relay IIJ is energized over a circuit which passes from terminal B at signal I2, through front contact II of relay I2H, reverse polar contact 4U-4I of relay IZH, back point of contact 42 of relay I2J, front contact 43 of relay`4TR, front contact 44 of relay STR, relay IIJ, front contact 34 of relay STR, front contact 35 of relay 4TR, front point of contact 36 of relay l2I-I, reverse polar contact 31-38 of relay IZH, and back point of contact 39 of relay I2J to terminal C.

When relay IIH is energized in the reverse direction and relay IIJ also is energized, relay IUH is energized in the normal direction over a circuit which passes from terminal B at signal II, through front point of contact 45 of relay IIJ, reverse polar contact 38-31 of relay I II-I, front point of contact 46 of relay I IH, front contact 4'I of relay 2TR, front contact 48 of relay ITR, relay IDH, front contact 49 of relay ITR, front contact 50 of relay 2TR, front point of contact 5I of relay IIH, reverse polar contact 30-29 or" relay IIH, and front point of contact 52 of relay IIJ to terminal C.

When relay IGH is energized in the normal direction, the polarized line circuit for the section next in rear of location W is energized in the normal direction over normal polar contacts 53-31 and 54-30 of relay IDH and over front points of contacts 55 and 56 of relay IGH so that the signal (not shown) for such section next in rear is also displaying the normal proceed indication.

When the train K vacates the section immediately to the right of location Z, relay I2J will become energized so that relay I IH will be energized in the normal direction to cause signal II to display the normal proceed indication.

The relays H are provided with the retained neutral feature so that tumble-down of the signal circuits tothe rear will be avoided during polechanging periods. For example, when the polarity of the polarized line circuit controlling relay I I H is changed from the reverse direction to the normal direction, the front points of contacts 46 and 5I of relay IIH will not become opened and, therefore, the energization of the polarized line circuit for the section W-X will not be disturbed.

It Will be noted that the relays J become energized only when the proceed circuit for the lower semaphore arm L of the associated signal is to be closed, so that, normally the signaling system embodying my invention requires energy only to energize the relays H and to maintain the upper semaphore arms U in the vertical position. Since this energy is relatively small and since under normal conditions the signals will be displaying the normal proceed indication for the greater portion of the time, it will be apparent that my system will be economical in current consumption. This will result in a material reduction in the cost of maintenance particularly when primary batteries are utilized as a source of energy.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a section of railway track, a iirst line circuit for said section including a pair of line wires, a second line circuit for said section including another line wire and one wire of said rst line circuit, track circuit means for said section for governing both said line circuits, means governed in accordance with trafc conditions in advance of said section for energizing only said iirst line circuit with current of reverse polarity or for energizing said second line circuit simultaneously with the energization or said iirst line circuit with current of said reverse polarity or for energizing only said first line circuit with current of normal polarity, a polarized relay governed by said rst line circuit, a neutral relay governed by said second line circuit, a signal for said section including one indication unit controlled only by said polarized relay and including another indication unit controlled by said polarized relay as Well as by said neutral relay.

2. In combination, a section of railway track, a iirst line circuit for said section including a pair of line Wires, a second line circuit for said section including another line wire and one wire of said rst line circuit, track circuit means for said section for governing both said line circuits, means governed in accordance with traic conditions in advance of said section for energizing only said iirst line circuit with current of reverse polarity or for energizing said second line circuit simultaneously with the energization of said first line circuit with current of said reverse polarity or for energizing only said first line circuit with current of normal polarity, a polarized relay governed by said first line circuit, a neutral relay governed by said second line circuit, a signal for said section including a rst and a second indication unit, a circuit for said rst unit including a front contact of said polarized relay, another circuit for said rst unit including a front neutral contact and a normal polar contact both of said polarized relay, and a circuit for 5 3. In combination, a section of railway' track provided with a track circuit including a track relay, a pair of line wir-es each includinga front contact of said track relay, a polarized relay connected to said pair `of line wires, another line l wire including a front contact of said track relay, a neutral relay connected to said other line wire and to one wire of said pair of wiresnneans governed in accordance with traffic conditions in advance of said section for energizing only said l pair of wires in the normal direction or for energizing only said pair of wires in the reverse direction or for energizing said otherline wire in the normal direction effective only when said pair of wires is energized in the reverse direction, a signal for said section including a first indication unit and a second indication unit, means including contacts only of said polarized relay for governing said first indication unit, and means including contacts of both said polarized and neutral relays for governing said second indication unit.

4. In combination, a forward section and a rear section of railway track, a polarized relay and a neutral relay, trafc controlled means for deenergizing both said relays or for energizing only said polarized relay in the reverse direction or for energizing said neutral relay simultaneously with the energization of said polarized relay in the reverse direction or for energizing only said polarized relay in the normal direction, a first line circuit for the rear section includinga pair of line Wires, a second line circuit for the rear section including another line wire and one wire of said first circuit, means for supplying said first linecircuit only with current in the reverse direction when. said polarized relay is deenergized, means for supplying said lirst line circuit with current in the reverse direction as well as for energizing said second line circuit eiective when i5 said polarized relay is energized in the reverse direction provided said neutral relay is then deenergized', means for supplying said first lin-e circuit only with current in the normal direction effective when said polarized relay is energized 50 in the reverse direction provided said neutral relay is then energized or when said polarized relay is energized in the normal direction, and traic governing means for the rear section governed by said two relays.

55 5. In combination, a forward section and a rear section of railway track, a polarized relay and a neutral relay, traiiic controlled means for reversibly energizing said polarized relay only or for energizing said neutral relay simultaneously 60 with the energization of said polarized relay, a pole changer controlled by said polarized relay, another pole changer controlled by said neutral relay, a first line circuit for the rear section governed by said two pol-e changers and including a 65 pair of line wires, a second line circuit for the rear section governed by both said neutral and said polarized relays and` including another line wire as well as one wire of. said pair of wires, and traffic governing means for the rear section gov- 70 erned by said two line circuits.

6. In combination, a forward section and a rear section of railway track, a polarized relay and a neutral relay, traffic controlled means for deenergizing both said relays or for energizing 75 only said polarized relay in the reverse direction or for energizing said neutral relay simultaneous'- ly with the energization of said polarized relay in the reverse direction or for energizing only said polarized relay in the normal direction, a first line circuit for the rear section including a pair of line wires, a second line circuit for the rear section including another line wire and one Wire of saidpair of wires, track circuit means for the rear section for controlling said two line circuits, means including al back contact of said polarized relay for supplying said first line `circuit with current in the reverse direction, means including a `front 'neutral contact and a reverse polar contact both of said polarized relay as well as a back contact of said neutral relay for also supplying said rst line circuit with current in the reverse direction, means including a front neutral contact and a reverse polar contact both of said polarized relay as well as a front contact of said neutral relay for supplying said first line circuit with current in the normal direction, means including a front contact and a `normal polar contact both of said polarized relay for supplying said first line circuit with current in the normal direction, and means including a front neutral contact and a reverse polar contact both of said polarized relay as well as a back contact of said neutral relay for energizing said second line circuit, and signaling means for said rear section controlled by said rst and second linc circuits.

7. In combination, a forward section and a rear section of railway track, a polarized relay and a neutral relay, traffic controlled means for deenergizing both said relays or for energizing only said polarized relay in the reverse direction or for energizing said neutral relay simultaneous- `ly with the energization of said polarized relay in the reverse direction or for energizing only said polarized relay in the normal direction, a first line circuit for the rear section including a pair of line wires, a second line circuit for the rear section including another line wire and one wire of said pair of wires, track circuit means for the rear section for controlling said two line circuits, a set of pole changing contacts on said neutral relay connected to a source of energy, means including a front neutral contact and a reverse polar contact both of said polarized relays for connecting said first line circuit toi said pole changing contacts, another reverse polar contact of said polarized relay connected to said sourceof energy by a frontneutral contact of said polarized relay, means including a back contact of said neutral relay for connecting said second line circuit to said other reverse polar contact, and signaling means for the rear section governed by said rst and second line circuits.

8. In combination, a forward section and a rear section of railway track, a polarized relay and a neutral relay, traffic controlled means for deenergizing both said relays or for energizing only said polarized relay in the reverse direction or for energizing said neutral relay simultaneous-- ly with the energization of said polarized relay in the reverse direction or for energizing only said polarized relay in the normal direction, a first line circuit for the rear section including a pair of line wires, a second line circuit for the rear section including another line wire and one wire of said pair of wires, track circuit means for the rear section for controlling said two line circuits, means including contacts of said polarized relay for reversibly governing said first line circuit, means including a set of pole changing contacts of said neutral relay also for governing said rst line circuit, means governed by said polarized and neutral relays for governing said second line circuit, and traffic governing means for the rear section controlled by said first and second line circuits.

9. A railway signal system comprising a stretch of railway track divided into sections, a polarized line circuit for each section including a pair of line wires, a neutral line circuit for each section including another line Wire and one wire of said pair of wires, a polarized relay for each section governed by the associated polarized line circuit, a neutral relay for each section governed by the associated neutral line circuit, traffic governing means for each section governed by the associated polarized and neutral relays, means effective when one section is occupied to supply only the polarized line circuit for the section rst in rear of such occupied section with current of one polarity, means then effective to supply the polarized line circuit for the section second in rear of such occupied section With current of said one polarity as well as to energize the neutral line circuit for such second section in rear, and means then effective to supply only the polarized line circuit for the section third in rear of such occupied section with current of the opposite polarity.

l0. In combination, a section of railway track, a iirst line circuit for said section including a pair of line wires, a second line circuit for said section including another line wire and one wire of said pair of wires, track circuit means for said section for governing said two line circuits, means for energizing only said first line circuit or forenergizing said second line circuit simultaneously withthe energization of said first line circuit in accordance with traffic conditions in advance of said section, a rst relay governed by said first line circuit and a second relay governed by said line circuit, and a signal for said section controlled by said two relays in such a manner as to display a normal proceed indication when said iirst relay only is energized and a more restrictive proceed indication when both said relays are energized.

11, A railway signal system comprising a first and a second as well as a third and a fourth track section over which traflic normally progresses in the order named, a first and a second line circuit for each section, means for opening the line circuits for the fourth section when that section is occupied, means then effective to supply only the iirst line circuit for the third section with current of one polarity, means then effective to supply the first line circuit for the second section With current of said one polarity as well as to energize the second line circuit for the second section, means then effective to supply only the rst line circuit for the rst section with current of the other polarity, a polarized relay connected directly to the rst line circuit for the iirst section, a neutral relay connected directly to the second line circuit for the iirstsection, and a signal for the rst section controlled by said two relays.

12. In combination, a stretch of railway track divided into a plurality of track sections, a polarized line circuit for each section including a pair of conductors, a neutral line circuit for each section including a pair of conductors one of which is also one of the rst mentioned pair, traflc controlled means for each section for governing the associated polarized and neutral line circuits, means effective when one section is occupied to supply only the polarized line circuit for the section next in rear of such occupied section with current in one direction, means then and only then effective to energize the neutral line circuit for the section second in rear of such occupied section as well as to supply the polarized line circuit for such section second in rear with current in said one direction, and means then effective to supply only the polarized line circuit for the section third in rear of such occupied section with current in the opposite direction.

13. In combination, a stretch of railway track divided into a plurality of track sections, a polarized line circuit for each section including a pair of conductors, a neutral line circuit for each section including a pair of conductors one of which is also one of the iirst mentioned pair, traino controlled means for each section for governing the associated polarized and neutral line circuits, means effective when one section is occupied to supply only the polarized line circuit for the section next in rear of such occupied section with current in one direction, means then and only then effective to energize the neutral line circuit for the section second in rear of such occupied section as Well as to supply the polarized line circuit for such section second in rear with current in said one direction, means then effective to supply only the polarized line circuit for the section third in rear of such occup-ied section with current in the opposite direction, and signaling means for each section governed by the associated line circuits and capable of displaying at least three different proceed indications.

GEORGE R. PFLASTERER. 

